Showing papers on "Reverse osmosis published in 2005"
TL;DR: In this article, the authors present a review of various systems that use renewable energy sources for desalination, including solar collectors, photovoltaics, solar ponds and geothermal energy.
949 citations
TL;DR: In this paper, a forward (direct) osmosis (FO) desalination process is presented, which uses an ammonium bicarbonate draw solution to extract water from a saline feed water across a semi-permeable polymeric membrane.
943 citations
TL;DR: In this paper, the authors reviewed the literature on the fouling phenomena in reverse osmosis (RO) membrane systems, the analytical techniques used to quantify fouling, preventive methods, and membrane cleaning strategies and made specific recommendations on how scientists, engineers, and technical staff can assist in improving the performance of these systems through fundamental and applied research.
Abstract: Desalination by using reverse osmosis (RO) membranes has become very popular for producing freshwater from brackish water and seawater. Membrane lifetime and permeate flux, however, are primarily affected by the phenomena of concentration polarization and fouling at the membrane surface. The scope of the current paper was to critically review the literature on the fouling phenomena in RO and ultrafiltration (UF) membrane systems, the analytical techniques used to quantify fouling, preventive methods, and membrane cleaning strategies. The paper also makes specific recommendations on how scientists, engineers, and technical staff can assist in improving the performance of these systems through fundamental and applied research.
468 citations
TL;DR: In this article, the authors evaluated the performance of an industrial-type capacitated deionization technology (CDT) module for brackish water desalination and concluded from test results and an associated cost evaluation that CDT could be an alternative desaline technology in the near future.
449 citations
TL;DR: In this paper, an innovative system that combines three different membrane processes for reclamation and reuse of wastewater in future space missions was evaluated, and the conditions for minimum energy consumption were determined and used in estimating the specific energy cost of treating the wastewater generated in space.
283 citations
TL;DR: In this paper, a dual membrane contactor process for treatment of combined hygiene and metabolic wastewater was investigated and it was demonstrated that water flux could be increased by up to 25 times with only a 3-5 C temperature difference across the membranes.
260 citations
TL;DR: The results of the over 3 years' time research on the direct contact membrane distillation applied for production of the demineralised water have been presented in this article, where the hydrophobic capillary polypropylene membranes (Accurel PP S6/2) were used in these studies.
256 citations
TL;DR: In this paper, a numerical concentration polarization model was developed to enable local description of permeate flux and solute rejection in cross-flow reverse osmosis separations, and predictions of channel averaged water flux and salt rejection by the developed numerical model, the classical film theory model, and a recently proposed analytical model were compared to well-controlled laboratory scale experimental data.
241 citations
TL;DR: In this paper, the feasibility of applying reverse osmosis (RO) membrane separation to reduce fluoride load to less than 1 kg/d was investigated, and the design parameters of a small RO separation unit were estimated.
240 citations
TL;DR: In this article, the removal of arsenic and pesticides from natural ground water from the Slavonia region, Croatia, by two commercial nanofiltration membranes (NF270 and NFc) was investigated.
220 citations
TL;DR: In this paper, the results obtained from laundry wastewater treatment using conventional methods namely precipitation/coagulation and the flocculation process with adsorption on granular-activated carbon (GAC) and an alternative method, membrane filtrations, namely ultrafiltration (UF) and reverse osmosis (RO).
Abstract: This paper presents the results obtained from laundry wastewater treatment using conventional methods namely precipitation/coagulation and the flocculation process with adsorption on granular-activated carbon (GAC) and an alternative method, membrane filtrations, namely ultrafiltration (UF) and reverse osmosis (RO). Chemical analyses showed that parameter values of untreated wastewater like temperature, pH, sediment substances, total nitrogen and phosphorous, COD, BOD5, and the amount of anion surfactants had been exceeded in regard to Slovenian regulation. These regulations can be used as requirements for wastewater reuse and make treated wastewater an available source for the existing water supply. The study of conventional treatment was based on a flocculation with Al2(SO4)3·18H2O and adsorption on GAC. Membrane filtrations were studied on a pilot wastewater treatment plant: ultrafiltration (UF) and reverse osmosis (RO) units. The membranes used in this experiment were ceramic UF membrane and spiral wounded – polyethersulfone – RO membranes. The quality of the wastewater was improved by both methods and the specifications of a concentration limit for emission into water were confirmed. The disadvantage of GAC is that there is no possibility of any kind of selection, which is essential for recycling and re-use, while permeate coming from RO met the required regulation as well as requirements for reusing in washing process. However, the economical analyses showed that the membrane filtrations are more expensive compared to the GAC treatment process.
TL;DR: In this article, the optimal operating conditions for COD, color, salt rejection and permeate flux were investigated and the feasibility of nanofiltration and reverse osmosis membrane combined process was evaluated.
TL;DR: In general, the presence of effluent organic matter (EfOM) improved the rejection of ionic organics by tight NF and RO membranes, as compared to a type-II water matrix (adjusted by ionic strength and hardness), likely as a result of a decreased negatively charged membrane surface.
Abstract: The rejection of emerging trace organics by a variety of commercial reverse osmosis (RO), nanofiltration (NF), and ultra-low-pressure RO (ULPRO) membranes was investigated using TFC-HR, NF-90, NF-200, TFC-SR2, and XLE spiral membrane elements (Koch Membrane Systems, Wilmington, Massachusetts) to simulate operational conditions for drinking-water treatment and wastewater reclamation In general, the presence of effluent organic matter (EfOM) improved the rejection of ionic organics by tight NF and RO membranes, as compared to a type-II water matrix (adjusted by ionic strength and hardness), likely as a result of a decreased negatively charged membrane surface Rejection of ionic pharmaceutical residues and pesticides exceeded 95% by NF-90 XLE, and TFC-HR membranes and was above 89% for the NF-200 membrane Hydrophobic nonionic compounds, such as bromoform and chloroform, exhibited a high initial rejection, as a result of both hydrophobic-hydrophobic solute-membrane interactions and steric exclusion, but rejection decreased significantly after 10 hours of operation because of partitioning of solutes through the membranes This resulted in a partial removal of disinfection byproducts by the RO membrane TFC-HR In a type-II water matrix, the effect of increasing feed water recoveries on rejection of hydrophilic ionic and nonionic compounds was compound-dependent and not consistent for different membranes The presence of EfOM, however, could neutralize the effect of hydrodynamic operating condition on rejection performance The ULPRO and tight NF membranes were operated at lower feed pressure, as compared to the TFC-HR, and provided a product water quality similar to a conventional RO membrane, regarding trace organics of interest
TL;DR: In this paper, a mathematical model for the desalination of brackish water through controlled potential electrodialysis has been developed, which allows to predict the behaviour of the system, calculate the electrical energy consumption and calculate the necessary time for successful desalinization.
TL;DR: In this article, the state-of-the-art of simple and fully integrated hybrid desalination systems is reviewed, which are characterized by flexibility in operation, less specific energy consumption, low construction cost, high plant availability and better power and water matching.
TL;DR: In this paper, the authors focused on the concentration of 1/3 diluted skimmed milk (chemical oxygen demand, COD ≈ 36 g O2/L) to about 1/1 milk (volume reduction factor, VRF 3), with nine nanofiltration and reverse osmosis membranes by dead-end filtration.
TL;DR: In this paper, the authors proposed the use of UF membrane technology to produce high quality pretreated feedwater for Reverse Osmosis (RO) desalination plants, which allows them to operate on a continuous basis, at high and stable fluxes, at higher recovery rates, and also allow a better control of Boron limit values.
TL;DR: Key factors which have been determined to result in successful operation of large-scale plants, and data from major RO wastewater treatment plants will be presented to show how the RO membranes operate under actual conditions, utilizing many of these design features.
TL;DR: In this article, the salinity effect on different RO elements treating different feed waters is analyzed and the results of the study on individual elements are used to accurately predict the salt passage in an existing full scale RO system.
TL;DR: A novel global optimization algorithm to solve nonconvex problem is used to find the global optimal design of reverse osmosis networks for seawater desalination to determine the optimal process design and operating conditions for a given water production.
TL;DR: The membrane area is the most important decision variable in designing a spiral wound module for desalination of brackish water as well as seawater, whereas ΔP is the best decision variable for a tubular module for the desalinated water (where the quality of the permeate is of prime importance).
TL;DR: In this paper, the performance of microfiltration, ultra-filtration (UF), nanofiltration (NF), and reverse osmosis (RO) was evaluated in a paper mill in Italy.
Patent•
13 Sep 2005TL;DR: In this article, a process and system for purifying water is described, where an ion exchange takes place between the divalent salt and another salt, such as a monovalent salt to produce two concentrated salt streams that contain salts having greater solubility in water than the Divalent salt.
Abstract: A process and system for purifying water is disclosed. For example, in one embodiment, the process may be used to remove a divalent salt, such as calcium sulfate, from a water source in order to prevent the divalent salt from precipitating during the process. The water source, for instance, may be fed to an ion separating device, such as an electrodialysis device. In the electrodialysis device, an ion exchange takes place between the divalent salt and another salt, such as a monovalent salt to produce two concentrated salt streams that contain salts having greater solubility in water than the divalent salt. In one embodiment, the two salt streams that are produced may then be combined to precipitate the divalent salt in a controlled manner. During the process, various other components contained within the water feed stream may also be removed from the stream and converted into useful products. In one particular embodiment, the process is configured to receive a byproduct stream from a reverse osmosis process.
TL;DR: This study has shown that high quality reuse water can be produced from municipal wastewater through the use of an MBR-RO system, and a denitrification step in the MBR should be considered in potable water applications.
TL;DR: In this paper, the authors compared one-stage and two-stage (NF + RO and RO + RO) spiral-wound membrane treatments with five model process waters representative of the main composition variations observed in dairies.
TL;DR: In this article, the authors discuss the economic and technical differences of the various processes for remineralization and discuss the advantages and disadvantages of the different processes, as well as the client experiences with the competing processes.
TL;DR: In this article, the authors take a glance at the fluid effluents analysis-data from two MSF plants and two RO plants around the Arabian Gulf compared-against the Standard of Industrial Effluents limits for the Kingdom of Bahrain, and attempt to highlight the invisible dangers of desalination fluid-effluents.
TL;DR: Commercial available NF and RO membranes are tested on laboratory scale to remove nutrients from anaerobically treated black water in order to meet the Dutch guidelines for ammonium and phosphate.
TL;DR: In this article, a feed-forward neural network (NN) model is developed to predict the performance of a reverse osmosis (RO) experimental setup, which uses a FilmTec SW30 membrane.
TL;DR: In this article, the feasibility of using natural evaporation (without heat supply) opposite to conventional Evaporation for concentrating brines from brackish desalination plants is evaluated.